Probably it was just the heat expanding the air inside, causing it to pop. If it was dry, the the heat could build up pretty quickly with no venting.However, I have to admit that I have never seen or heard of that happening before.

One question...you say your alternator cooked itself because it was run dry? The rotor and stator aren't in contact, so I didn't think it'd be a problem. Always thought that the primary chain and clutch plates (on the stock wet clutch, anyhow) were the reasons for the lubrication.

One question...you say your alternator cooked itself because it was run dry? The rotor and stator are in contact, so I didn't think it'd be a problem. Always thought that the primary chain and clutch plates (on the stock wet clutch, anyhow) were the reasons for the lubrication.

Ask as I was planning on running a dry clutch from Newby.

You can run a dry clutch and dry primary, but you have to provide plenty of cooling vents when you do that. It can't be sealed up. It needs some air going over it.

I've been pondering this event ALLLLLLLLL night long. The only conclusion I could come to, is that somehow, the primary cover was never completely seated (it's been a cunt ever since it broke and I had to have it welded up) and all the ATF had slowly, or quickly, who effing knows, drained out of the primary which obviously had been causing some serious friction. I had noticed a small bit of smoke coming out of the hole where the alternator wires come out. I pulled over and stuffed my face an inch from my exhaust to get a whiff, wasn't electrical, metal or oil. I had smelled it before but couldn't pin point it and associated it with heat and the cold air and kept riding. I guess it was the smell of burning epoxy, and I got to smell it for over an hour waiting for the tow truck to show up. When you watch the video, the sound is extremely deadened due to a sensitive mic and loud exhaust. You really can't hear the exhaust at all in the video, yet my primary popped loud enough to be heard over the exhaust. So, is it possible that with the little amount of oil and the mass amount of heat that the ATF vaporized and ignited and actually BLEW my center nut off? I mean, I have a small bruise on my ankle bone this morning, it didn't just fall off. In fact, I'm pretty sure the guy in the utility truck I was passing thought I completely blew up my motor. It sounded like a gun shot when it went.

Some Enfields came with the crankcase breathers blowing into the crankcase and had breathers on the back of the primary cases to take care of the pressure. Over time some got replaced with the nonvented ones and blowing them off was not unusual! As for oil in the crankcase, the chain still needs it! I guess the oil could be used to cool the alternator, too.Don't know why you'd lose control of the bike because the primary blew off, especially if the oil was already gone and there was nothing to blow all over the real wheel, which can make things a bit sporty!Anyway, interesting clip!Bare